The investigators propose a new imaging method for children born with congenital anomalies of the urinary tract that is a rapid, injection-, sedation-, and radiation-free alternative: the quick renal MRI. This proposal hypothesizes that the quick renal MRI has high validity compared to current radiologic standard for renal infection and scarring, the 99mTechnetium-dimercaptosuccinic acid (99mTc- DMSA) renal scan in the detection of acute renal infections and scars. If the quick renal MRI is accurate, it could potentially replace the DMSA scan for those specific questions and ease the burden of testing for children with chronic renal disease. Findings from these studies will provide preliminary data and rationale for a multi-centered study to further test this new technology. Participants will be 0-21 years of age and can expect to be on study for from 1 week (if enrolled in Aim 1) to 6 months (if enrolled in Aim 2).